Neke brojke za one koje interesira ova tema R. M. Santilli Hydrogen International Conference, Munich 2000. (Excerpts) We recall that the use of hydrogen as fuel does resolve the environmental problems of fossil fuels due to excessive emissions of carcinogenic substances and carbon dioxide. However, the combustion of hydrogen originating from regeneration processes (e.g., from natural gas) implies the permanent removal from our atmosphere of oxygen in a directly usable form, a serious environmental problem called oxygen depletion, since the combustion turns hydrogen and oxygen into water whose separation to restore the original oxygen balance is prohibitive due to cost. We then show that a conceivable global use of hydrogen from the indicated regeneration origin in complete replacement of fossil fuels would imply the permanent removal from our atmosphere of 2.8875x107 metric tons of O2 /day, with consequential termination of all life forms in our planet in a few years. As is well known, gasoline combustion requires atmospheric oxygen, which is then turned into CO2 and various HydroCarbon (HC). In turn, CO2 is recycled by plants via the known reaction H2O + CO2 +(hv) -> O2 + (-(CH2O)-), which restores oxygen in the atmosphere. Essentially this was the scenario at the beginning of the 20th century. The same scenario at the beginning of the 20th century is dramatically different, because forests have rapidly diminished while we have reached the following unreassuringly daily consumption of crude oil 74.18 million of barrel per day = (1) = (74.18 million barrels/24h)x(55 gallons/barrel) = 4.08x109 gallons/24h = 1.54x 1013 cc/24h (using 4 quarts/gallon and 946 cc/quart) = = (4.08 x 109 gallons)x(4 qrt./gallon)x(946 cc/qrt.)/day = 1.5438 x 1013 cc/day = (1.5438 x 1013 cc/day)x(0.7028 grams/cc)= 1.0850 x 1013 grams octane/day = (1.0850 x 1013 grams)/(114.23 grams/mole) = 9.4984 x 1010 moles n-octane/day, (see, e.g., http://www.eia.doe.gov/emeu/international/energy.html) where we have replaced, for simplicity, crude oil with a straight chain of n-octanes CH3-(CH2)6-CH3 with the known density of 0.7028 g/cc at 20o C. It should be indicated that data (1) do not include the additional large use of natural gas and coals, which would bring the daily combustion of all fossil fuel to the equivalent of about 120 million barrels of crude oil per day. The primary environmental problems caused by the above disproportionate consumption of fossil fuel per day are the following: 1) Excessive emission of carcinogenic and other toxic substances in the combustion exhaust. It is well known by experts that gasoline combustion releases in our atmosphere the largest percentage of carcinogenic and other toxic substances as compared to any other source. The terms "atmospheric pollution" are an euphemism for very toxic breathing. 2) Excessive release of carbon dioxide. It is evident that, under the very large daily combustion (1), plants cannot recycle the entire production of CO2, thus resulting in an alarming increase of CO2 in our atmosphere, an occurrence known as green house effect. In fact, by using the known reaction C8H18 + (25/2)O2 -> 8 CO2 + 9 H2O, we have the following alarming daily production of CO2 from fossil fuel combustion: (9.4984 x 1010 moles C8H18)x(8/1)/day = 7.5987 x 1011 moles CO2/day = = (7.5987 x 1011 moles) x (0.044 Kg/mole)/day= 3.3434 x 107 Kg/day = (2) = (3.3434 x 1010 Kg/day)/(1000 Kg/metric ton) = 3.3434x107 metric tons/day It is evident that plants cannot possibly recycle such a disproportionate amount of daily production of CO2. This has implied a considerable increase of CO2 in our atmosphere which can be measured by any person seriously interested in the environment via the mere purchase of a CO2 meter, and then compare current readings of CO2 with standard values on record, e.g., the percentage of CO2 in our atmosphere at sea level in 1950 was 0.033 % ± 0.01 % (see, e.g., Encyclopedia Britannica of that period). Along these lines, in our laboratory in Florida we measured a thirty fold increase of CO2 in our atmosphere over the indicated standard. We assume the reader is aware of recent TV reports of; an occurrence, which has never been observed before. Increasingly catastrophic climactic events are known to everybody. 3) Excessive removal of directly usable oxygen from our atmosphere, an environmental problem of fossil fuel combustion, which is lesser known than the green house effect, even among environmentalists, but potentially more serious. The problem is called oxygen depletion, and refers to the difference between the oxygen needed for the combustion less that expelled in the exhaust. By using again the reaction C8H18 + (25/2)O2 -> 8 CO2 + 9 H2O and data (2), it is easy to obtain the following additionally alarming daily use of oxygen for the combustion of fossil fuel (9.4984 x 1010 moles octane/day)x(12.5 moles O2/1 mole octane) = = 1.1873 x 1012 moles of O2/day = (1.1873 x 1012 moles of O2)x(0.032 Kg/mole O2)= (3) = 3.7994 x 1010 kg O2/day = 3.7994 x 107 metric tons/day. Again, this large volume of oxygen is turned by the combustion into CO2 of which only an unknown part is recycled by plants into usable oxygen. Thus, the actual and permanent oxygen depletion caused by fossil fuel combustion in our planet is currently unknown. However, it should be indicated that the very existence of the green house effect is unquestionable evidence of oxygen depletion, because we are dealing precisely with the quantity of CO2 which has not been re-converted into O2 by plants. Oxygen depletion is today measurable by any person seriously interested in the environment via the mere purchase of an oxygen meter, measure the local percentage of oxygen, and then compare the result to standards on record, e.g., the oxygen percentage in our atmosphere at sea level in 1950 was 20.946% ± 002% (see, e.g., Encyclopedia Britannica of that period). Along these lines, in our laboratory in Florida we measure a local oxygen depletion of 3%-5%. Evidently, bigger oxygen depletions are expected for densely populated areas, such as Manhattan, London, and Tokyo, or at high elevation. We assume the reader is aware of the recent decision by U.S. airlines to lower the altitude of their flights despite the evident increase of cost. This decision has been apparently motivated by oxygen depletion, e.g., fainting spells due to insufficient oxygen suffered by passengers during flights at previous higher altitudes. The purpose of this note is to indicate that, whether used for direct combustion or in fuel cells, hydrogen produced from regeneration methods (e.g., from natural gas) does avoid the release carcinogenic substances and carbon dioxide in the exhaust, but causes an alarming oxygen depletion which is considerably bigger than that caused by fossil fuel combustion under the same energy output. This depletion is due to to the fact that gasoline combustion turns atmospheric oxygen into CO2 part of which is recycled by plants into O2, while hydrogen combustion turns atmospheric oxygen into H2O. This process permanently removes oxygen from our atmosphere in a directly usable form due to the excessive cost of water separation to restore the original oxygen balance. By assuming, for simplicity, that gasoline is solely composed of one octane C8H18, thus ignoring other isomers, the combustion of one mole of H2 gives 68.32 Kcal, while the combustion of one mole of octane produces 1,302.7 Kcal. Thus, we need 19.07 = 1302.7 / 68.32 moles of H2 to produce the same energy of one mole of octane. In turn, the combustion of 19.07 moles of H2 requires 9.535 moles of O2, while the combustion of one mole of octane requires 12.5 moles of O2. Therefore, on grounds of the same energy release, the combustion of hydrogen requires less oxygen than gasoline (about 76% of the oxygen consumed by the octane). The alarming oxygen depletion occurs, again, because of the fact that the combustion of hydrogen turns oxygen into water, by therefore permanently removing usable oxygen from our planet. When used in modest amounts, the combustion of hydrogen constitutes no appreciable environmental problem. However, when used in large amounts, the combustion of hydrogen produced via regenerative methods is potentially catastrophic on environmental grounds, because oxygen is the foundation of life. At the limit, a global combustion of hydrogen of regenerating origin in complete replacement of fossil fuels would render our planet uninhabitable in a short period of time. In fact, such a vast use would imply the permanent removal from our atmosphere of 76% of the oxygen currently consumed to burn fossil fuels, i.e., from Eqs. (2) and (3), we would have the following permanent oxygen depletion due to global hydrogen combustion: 76% oxygen used for fossil fuel combustion = (4) = 2.8875 x 107 metric tons O2 depleted/day. In addition, one should take into account the quantitatively similar oxygen depletion caused by the production of electricity, resulting in a truly catastrophic oxygen depletion which would imply the termination of any life on Earth within a few years. Predictably, the above feature of hydrogen combustion has alarmed environmental groups, labor unions, and other concerned people. As an illustration, calculations show that, in the event all fuels in Manhattan were replaced by hydrogen, the local oxygen depletion would cause heart failures, with evident large financial liabilities and legal implications for hydrogen suppliers. In addition to the above catastrophic oxygen depletion, hydrogen produced via regenerating processes has additional, equally serious environmental problems of carcinogenic and CO2 emission pointed out by P. Spath and M. Mann of the U. S. National Renewable Energy Laboratory at the recent International Hydrogen Energy Forum 2000 [1]. The combustion of hydrogen produced from the electrolytic separation of water via electricity originating from conventional power plants, has similar environmental problems. In fact, the original separation of the water, and its subsequent recombination in the combustion does indeed preserve the original oxygen balance. However, an oxygen depletion greater than that of Eq. (4) is caused by the combustion of fossil fuels to produce the electricity needed for the separation of water. Moreover, the combustion of fossil fuels in primary power plants implies the emission of large amounts of carcinogenic substances and carbon dioxide. As a result, the automotive use of hydrogen whose production requires electricity originating from conventional power plants is more polluting than gasoline. The only environmentally acceptable use of hydrogen as fuel is that produced via the separation of water whose electricity originates from clean, renewable, primary sources of energy, such as wind and solar energies, as suggested by the BMW Group for their hydrogen powered car [2]. Unfortunately, the latter sources of primary energy have insufficient production capabilities for large scale automotive use of hydrogen. This scenario implies that the primary environmental problems currently rest with primary sources of energy, thus suggesting primary research efforts in the search of new clean energy for the production of electricity Tu cekamo i napredak na polju supravodljivosti. Zdravko Dokuzovic distributed by CROWN - www.croatianworld.net - CroWorldNet@aol.com Notice: This e-mail and the attachments are confidential information.If you are not the intended recipient of this e-mail, you are hereby notified that any dissemination, distribution or copying of this e-mail and the attachments is strictly prohibited and violators will be held to the fullest possible extent of any applicable laws governing electronic Privacy. If you have received this e-mail in error please immediately notify the sender by telephone or e-mail, and permanently delete this e-mail and any attachments.
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